THE IMPLEMENTATION AND CONTROL OF HEXAPOD ROBOT WITH VISUAL OBSTACLE AVOIDANCE

• Main Authors: Chiau-Wei Huang, 黃喬瑋
• Other Authors: Wen-Shyong Yu
• Format: Others
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/12651884690540331234

碩士 === 大同大學 === 電機工程學系(所) === 101 === The main purpose of this thesis is to design a fuzzy control for a hexapod robot based on visual servo control to avoid obstacle. The implementation of the motion control for the hexapod robot using the inverse kinematics (IK) and visual recognition system is used to achieve the obstacle avoidance. The control structure is composed of three parts: image recognition, fuzzy control systems, and inverse kinematics for trajectory tracking and obstacle avoidance. First, the image processing is used to identify whether there are any obstacles in the front, and making it as a feedback to the control system. Then, the microcontroller will find out the rotation angles for each joint via IK to avoid obstacles. For image recognition, we use OpenCV to process environment to the grayscale and binarization, filter noise through erosion and dilation, and then fill all of the contours using Sobel edge detection, and finally calculate the area and compare with each other. It is regarded as an obstacle if the detected area is the biggest. We will construct a rule table based on the proportion of the size of the area to the actual distance between the obstacle and camera. Therefore, we can determine the actual distance to the obstacle by default trajectories. In contrast to the most previous motion control design methods for legged robots based on trial and error by directly sending the angle commands to each servo in accordance with the mechanical structure, we construct the inverse kinematics and dynamics model to enable the servo control system using the inverse kinematics to significantly reduce the complexity of the motion control design.